================================================================== BUG: KASAN: use-after-free in btrfs_printk+0x421/0x46b fs/btrfs/super.c:245 Read of size 8 at addr ffff888027fb86a0 by task syz-executor.5/8617 CPU: 1 PID: 8617 Comm: syz-executor.5 Not tainted 5.9.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1d6/0x29e lib/dump_stack.c:118 print_address_description+0x6c/0x640 mm/kasan/report.c:385 __kasan_report mm/kasan/report.c:545 [inline] kasan_report+0x136/0x1e0 mm/kasan/report.c:562 btrfs_printk+0x421/0x46b fs/btrfs/super.c:245 device_list_add+0x1a94/0x1d60 fs/btrfs/volumes.c:943 btrfs_scan_one_device+0x2e1/0x460 fs/btrfs/volumes.c:1366 btrfs_mount_root+0x46e/0xb60 fs/btrfs/super.c:1634 legacy_get_tree+0xea/0x180 fs/fs_context.c:592 vfs_get_tree+0x88/0x270 fs/super.c:1549 fc_mount fs/namespace.c:978 [inline] vfs_kern_mount+0xc9/0x160 fs/namespace.c:1008 btrfs_mount+0x345/0xa80 fs/btrfs/super.c:1732 legacy_get_tree+0xea/0x180 fs/fs_context.c:592 vfs_get_tree+0x88/0x270 fs/super.c:1549 do_new_mount fs/namespace.c:2875 [inline] path_mount+0x1799/0x29f0 fs/namespace.c:3203 do_mount fs/namespace.c:3216 [inline] __do_sys_mount fs/namespace.c:3424 [inline] __se_sys_mount+0x28c/0x320 fs/namespace.c:3401 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x4608aa Code: b8 a6 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 ad 89 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 8a 89 fb ff c3 66 0f 1f 84 00 00 00 00 00 RSP: 002b:00007f66fd621a88 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f66fd621b20 RCX: 00000000004608aa RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007f66fd621ae0 RBP: 00007f66fd621ae0 R08: 00007f66fd621b20 R09: 0000000020000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000020000000 R13: 0000000020000100 R14: 0000000020000200 R15: 0000000020016800 Allocated by task 8554: kasan_save_stack mm/kasan/common.c:48 [inline] kasan_set_track mm/kasan/common.c:56 [inline] __kasan_kmalloc+0x10e/0x140 mm/kasan/common.c:461 kmalloc_node include/linux/slab.h:577 [inline] kvmalloc_node+0x81/0xf0 mm/util.c:575 kvmalloc include/linux/mm.h:765 [inline] kvzalloc include/linux/mm.h:773 [inline] btrfs_mount_root+0xd1/0xb60 fs/btrfs/super.c:1613 legacy_get_tree+0xea/0x180 fs/fs_context.c:592 vfs_get_tree+0x88/0x270 fs/super.c:1549 fc_mount fs/namespace.c:978 [inline] vfs_kern_mount+0xc9/0x160 fs/namespace.c:1008 btrfs_mount+0x345/0xa80 fs/btrfs/super.c:1732 legacy_get_tree+0xea/0x180 fs/fs_context.c:592 vfs_get_tree+0x88/0x270 fs/super.c:1549 do_new_mount fs/namespace.c:2875 [inline] path_mount+0x1799/0x29f0 fs/namespace.c:3203 do_mount fs/namespace.c:3216 [inline] __do_sys_mount fs/namespace.c:3424 [inline] __se_sys_mount+0x28c/0x320 fs/namespace.c:3401 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 8554: kasan_save_stack mm/kasan/common.c:48 [inline] kasan_set_track+0x3d/0x70 mm/kasan/common.c:56 kasan_set_free_info+0x17/0x30 mm/kasan/generic.c:355 __kasan_slab_free+0xe8/0x120 mm/kasan/common.c:422 __cache_free mm/slab.c:3420 [inline] kfree+0x124/0x210 mm/slab.c:3758 deactivate_locked_super+0xa7/0xf0 fs/super.c:335 btrfs_mount_root+0x70e/0xb60 fs/btrfs/super.c:1678 legacy_get_tree+0xea/0x180 fs/fs_context.c:592 vfs_get_tree+0x88/0x270 fs/super.c:1549 fc_mount fs/namespace.c:978 [inline] vfs_kern_mount+0xc9/0x160 fs/namespace.c:1008 btrfs_mount+0x345/0xa80 fs/btrfs/super.c:1732 legacy_get_tree+0xea/0x180 fs/fs_context.c:592 vfs_get_tree+0x88/0x270 fs/super.c:1549 do_new_mount fs/namespace.c:2875 [inline] path_mount+0x1799/0x29f0 fs/namespace.c:3203 do_mount fs/namespace.c:3216 [inline] __do_sys_mount fs/namespace.c:3424 [inline] __se_sys_mount+0x28c/0x320 fs/namespace.c:3401 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 The buggy address belongs to the object at ffff888027fb8000 which belongs to the cache kmalloc-16k of size 16384 The buggy address is located 1696 bytes inside of 16384-byte region [ffff888027fb8000, ffff888027fbc000) The buggy address belongs to the page: page:00000000d102b51c refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x27fb8 head:00000000d102b51c order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfffe0000010200(slab|head) raw: 00fffe0000010200 ffffea00010d4408 ffffea0000e35408 ffff88800ec40b00 raw: 0000000000000000 ffff888027fb8000 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888027fb8580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888027fb8600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888027fb8680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888027fb8700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888027fb8780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================